213987806 has 16 divisors (see below), whose sum is σ = 340616016. Its totient is φ = 100477056.

The previous prime is 213987803. The next prime is 213987811. The reversal of 213987806 is 608789312.

213987806 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×213987806² = 91581562233387272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213987803) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9140 + ... + 22616.

It is an arithmetic number, because the mean of its divisors is an integer number (21288501).

Almost surely, 2^213987806 is an apocalyptic number.

213987806 is a deficient number, since it is larger than the sum of its proper divisors (126628210).

213987806 is a wasteful number, since it uses less digits than its factorization.

213987806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13963.

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 213987806 is about 14628.3220500507. The cubic root of 213987806 is about 598.1310417774.

The spelling of 213987806 in words is "two hundred thirteen million, nine hundred eighty-seven thousand, eight hundred six".